Upvote:15
If you in Germany ride a bicycle under influence of alcohol and your blood alcohol content is above 0.16% or the police deem you incapable of riding the bicycle without endangering others, the consequences are basically the same as if you had been driving a motorized vehicle. It is of no relevance that you were only riding 50-60m or that it was not your bicycle.
Expressing yourself in a letter will potentially only make matters worse, since you might admit to something the police is not yet aware of. You can not expect such a letter to have any significance for your defence.
If the accusations against you are factually correct and there are no obvious mitigating circumstances, you might be better admitting the crime and face the penalty. Otherwise, you should hire a lawyer for your defence. Unless you are entitled to a free lawyer, you must however consider that you have to pay the lawyer on top of any penalty you will get from the court.
As you pointed out in a comment, your BAC was measured to 0.166% and therefore above the absolute 0.16% limit. The charges against you are therefore not based on a subjective asses*m*nt of your capability to operate a bicycle. With a BAC that high, you must in addition to a fine also expect that your driver's license (or right to drive in Germany, in case you have a foreign license) will be revoked. If you really depend on your driver's license, e.g. to perform your occupation, the court have the option to give you some leeway and let you keep your license. In this case, you may also be better off hiring a lawyer to help you out.