I reckon the significance of conviction or non-conviction court results is no longer as great as it once was. It’s common for insurance companies to enquire about findings of guilt for relevant crimes, or even merely being charged. So too some employers ask for or even require criminal history checks that might record findings of guilt.
And various statutory provisions take effect following findings of guilt whether a court records a conviction or not. (Recording demerit points for driving offences is one minor example.)
Nevertheless, folks understandably prefer a court not records a conviction against their name.
One reason I’ve often heard raised is about the possibility of a conviction restricting future travel, especially to the USA.
I’m not sure of the exact answer to that, but from what I can find, I don’t think it’s as big an issue as is sometimes suggested.
The US State Department runs travel.state.gov with advice for travellers to the USA.
Visitor visas are granted to ‘aliens’ who are eligible to receive a visa.
(2) Criminal and related grounds
(A) Conviction of certain crimes
(i) In general Except as provided in clause (ii), any alien convicted of, or who admits having committed, or who admits committing acts which constitute the essential elements of—
(I) a crime involving moral turpitude (other than a purely political offense) or an attempt or conspiracy to commit such a crime, or
(II) a violation of (or a conspiracy or attempt to violate) any law or regulation of a State, the United States, or a foreign country relating to a controlled substance (as defined in section 802 of title 21),
(ii) Exception Clause (i)(I) shall not apply to an alien who committed only one crime if—
(I) the crime was committed when the alien was under 18 years of age, and the crime was committed (and the alien released from any confinement to a prison or correctional institution imposed for the crime) more than 5 years before the date of application for a visa or other documentation and the date of application for admission to the United States, or
(II) the maximum penalty possible for the crime of which the alien was convicted (or which the alien admits having committed or of which the acts that the alien admits having committed constituted the essential elements) did not exceed imprisonment for one year and, if the alien was convicted of such crime, the alien was not sentenced to a term of imprisonment in excess of 6 months (regardless of the extent to which the sentence was ultimately executed).
(B) Multiple criminal convictions
Any alien convicted of 2 or more offenses (other than purely political offenses), regardless of whether the conviction was in a single trial or whether the offenses arose from a single scheme of misconduct and regardless of whether the offenses involved moral turpitude, for which the aggregate sentences to confinement were 5 years or more is inadmissible.
(C) Controlled substance traffickers
Any alien who the consular officer or the Attorney General knows or has reason to believe—
(i) is or has been an illicit trafficker in any controlled substance or in any listed chemical (as defined in section 802 of title 21), or is or has been a knowing aider, abettor, assister, conspirator, or colluder with others in the illicit trafficking in any such controlled or listed substance or chemical, or endeavored to do so; or
(ii) is the spouse, son, or daughter of an alien inadmissible under clause (i), has, within the previous 5 years, obtained any financial or other benefit from the illicit activity of that alien, and knew or reasonably should have known that the financial or other benefit was the product of such illicit activity,
(D) Prostitution and commercialized vice
Any alien who—
(i) is coming to the United States solely, principally, or incidentally to engage in prostitution, or has engaged in prostitution within 10 years of the date of application for a visa, admission, or adjustment of status,
(ii) directly or indirectly procures or attempts to procure, or (within 10 years of the date of application for a visa, admission, or adjustment of status) procured or attempted to procure or to import, prostitutes or persons for the purpose of prostitution, or receives or (within such 10-year period) received, in whole or in part, the proceeds of prostitution, or
(iii) is coming to the United States to engage in any other unlawful commercialized vice, whether or not related to prostitution,
So, this seems to exclude entry to people convicted of offences of moral turpitude (a broad term meaning conduct considered contrary to community standards of justice, honesty or good morals), drug users, people convicted of 2 or more offences of any type and imprisoned for 5 or more years, drug traffickers, and prostitutes and vice-related offenders.
edit And, following on from Dr Manhattan’s comment below, it is indeed the case that the meaning of conviction for aliens includes a finding of guilt: see 8USC1101(a)(48). That states:
(A) The term “conviction” means, with respect to an alien, a formal judgment of guilt of the alien entered by a court or, if adjudication of guilt has been withheld, where—
(i) a judge or jury has found the alien guilty or the alien has entered a plea of guilty or nolo contendere or has admitted sufficient facts to warrant a finding of guilt, and
(ii) the judge has ordered some form of punishment, penalty, or restraint on the alien’s liberty to be imposed.
(B) Any reference to a term of imprisonment or a sentence with respect to an offense is deemed to include the period of incarceration or confinement ordered by a court of law regardless of any suspension of the imposition or execution of that imprisonment or sentence in whole or in part.
Which means for the purpose of obtaining a visa to enter the USA, the distinction between conviction and non-conviction for prescribed offences is effectively meaningless.