A few comments 1/x
In a variety of cases, Brexit starts to reach EU court | Article [AMP] | Reuters uk.reuters.com/article/uk-bri…
Not from a Spanish court, but challenging the EU agency based in Spain. (nb: normally you can't raise a new point on appeal)
In practice that means an average 16 month wait for a judgment (ie May 2019) instead of four months.
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Here's the Brexit point - just because the UK "may" leave the EU isn't enough to justify a fast track process.
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theguardian.com/politics/2018/…
Actually David Davis removed himself from the case when he joined cabinet (Tom Watson remained a party). Analysis of the ECJ judgment here: eulawanalysis.blogspot.co.uk/2016/12/data-r…
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Here's a summary of their main arguments...
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But no one can be sure what courts will say & there are likely more cases to come /