I'll take a crack at this!

So as with many legal systems things do change over time. If we speak pre 1958... Well your prospects were not that good. While some Soviet civil law was extremely similar to civil law of countries like France or Germany which is you might think is strange. Why yes it is strange because writing a whole new law code is hard and the Soviets weren't exactly the most... Free of nation's.

So while similar in certain concepts of Western civil law there were clear differences rooted in pre revolution structures and it's structural integrity so to speak was based on Marxism-Leninism. So going off topic these kinds of law are exactly why the Russian/Soviet leadership and police forces get off Scott free most of the time... Soviet and possibly even modern Russian (only reason I say possibly is because while it's generally believed to be true I can't truly verify) are based on older systems which revolved around yet another secret police which the Tsars used to maintain order. This structure doesn't necessarily paint a pretty picture for you as a Soviet citizen here.

So now we move in to Soviet rule of law and civil liberties and such. Oh wait that's right aside from the changes in 1958 in terms of when you are allowed your legal counsel these did not exist in a traditional sense. Criminal cases were based on finding the truth and not exactly proving innocence or guilt and many powers were granted in relation to doing this. While no direct force was allowed, extensive questioning and solitary confinent was allowed for up to 10 days and straight up internment was allowed for a period of up to 9 months. So one or the other or both of those things could happen to you and the trial regardless of the laws regarding detention should be relatively fair.

Civil cases were a walk in the park compared to this as counsel was allowed at all times and generally speaking did not result in anything major which would lead towards a serious issue with the government or Soviet court system. This was person to person issues.

In both civil and criminal cases your case would be heard by a long term professional 5 year term judge alongside 2 lay judges which served 2.5 year terms. The witnesses would be called, investigated, evidence would be evaluated and and believe it or not you would be considered innocent until proven guilty but not exactly in a common law sense. The need to find the truth rather than protect legal rights is where this gets a tad fuzzy as it could go anywhere for you. However your court case was voted by a majority so you did have a relatively good chance in normal criminal and civil cases.

Now we get to the fun part.. are you a Kulak that survived the purges? Are you an enemy of the state or accused spy. Is Stalin still alive and you got on his bad side?? The clear answer here is if you have gathered interest from the government in any way you are more or less done for.. not necessarily dead, but definitely going to be sucked up Into a show trial and sent to a gulag. If you have gained their attention under Stalin you have a pretty good shot of being directly on one of Berias famous lists and shot, tortured or murdered gruesomely.

If you survive past the 50s your chances get a bit better since there were court and law reforms in the 60s which were a tad more helpful to the general everday man and part of destalinization

[5] Richard Pipes Russia Under the Bolshevik Regime, Vintage books, Random House Inc., New York, 1995, ISBN 0-394-50242-6, pages 402–403

Berman, H. J. (2007). "The Comparison of Soviet and American Law". American Business Law Journal. 1: 68–76. doi:10.1111/j.1744-1714.1963.tb01183.x.

Christopher Osakwe (1977) "Due Process of Law and Civil Right Cases in the Soviet Union", Soviet Law After Stalin..: The Citizen and the State in contemporary Soviet law. 1. Brill. ISBN 9-028-60679-3, pages 179-222.