from Maryland Politics by Annie Linskey
Glancing at a text message or an email from behind the wheel will cost $500 in fines starting Saturday when a new law goes into effect clarifying Maryland’s muddled driving-while-texting rules.
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Maryland drivers also aren’t supposed to talk on their cell phones per a year-old law, but doing so is remains a “secondary offense” meaning police can only pull over a driver who is also breaking another rule.
Drivers will still be able to use GPS systems on their phone while driving, or text an emergency operator.
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https://weblogs.baltimoresun.com/news/local/politics/2011/09/reading_a_text_message_or.htmloldId.20110930150028608

I believe, officially, the "3-foot law" goes into effect and the "manslaughter by vehicle or vessel" as well.
iodaniell
Our 3 foot law went into effect last year at this time but you are correct the Manslaughter by vehicle or vessel went into effect.
A blast from the past when MVA was publishing the "poor" summary of our 3′ law as outlined here:
https://www.baltimorespokes.org/article.php?story=20101005122814769
Just one of of many things Baltimore Spokes has championed to correct.